package com.icbc.cc.api;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLEncoder;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class FileDownload
 */
public class FileDownload extends HttpServlet {
	private static final long serialVersionUID = 1L;
    
	 private String contentType = "text/html;charset=utf-8";
	 private String enc = "utf-8";
	 private String fileRoot = "";
	 /**
     * 初始化contentType，enc，fileRoot
     */
    public void init(ServletConfig config) throws ServletException {
        String tempStr = config.getInitParameter("contentType");
        if (tempStr != null && !tempStr.equals("")) {
            contentType = tempStr;
        }
        tempStr = config.getInitParameter("enc");
        if (tempStr != null && !tempStr.equals("")) {
            enc = tempStr;
        }
        tempStr = config.getInitParameter("fileRoot");
        if (tempStr != null && !tempStr.equals("")) {
            fileRoot = tempStr;
        }
    }
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doPost(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		//String filepath = request.getParameter("filepath");
       //String fullFilePath = fileRoot + filepath;
        /*读取文件*/
        File file = new File(request.getParameter("filePath"));
        /*如果文件存在*/
        if (file.exists()) {
        	String filename = URLEncoder.encode("测试.pdf", enc);
        	
            response.reset();
            response.setContentType(contentType);
            response.setCharacterEncoding("utf-8");
            response.setHeader("Content-disposition","attachment;filename=\""+filename+"\"");
            int fileLength = (int) file.length();
            response.setContentLength(fileLength);
            /*如果文件长度大于0*/
            if (fileLength != 0) {
                /*创建输入流*/
                InputStream inStream = new FileInputStream(file);
                byte[] buf = new byte[4096];
                /*创建输出流*/
                ServletOutputStream servletOS = response.getOutputStream();
                int readLength;
                while (((readLength = inStream.read(buf)) != -1)) {
                    servletOS.write(buf, 0, readLength);
                }
                inStream.close();
                servletOS.flush();
                servletOS.close();
            }
        }
	}

}
